This and other similar articles address potential inconsistencies encountered by a certain religious view. While I see them as inconsistencies, for others they may pose no problem at all. For this reason, the articles are entitled "Possible difficulties in [this or that religion]" and not "Contradictions in [this or that religion]". Each of these articles is a list of possible difficulties with short comments aimed at encouraging critical thinking on each issue.

The plurality of souls (purushas)

Since the self in Samkhya-Yoga metaphysics is devoid of any attributes that could individualize it, no difference can be made between one purusha and another, and therefore their plurality is problematic. S. Radhakrishnan writes:

The self is without attributes or qualities, without parts, imperishable, motionless, absolutely inactive and impassive, unaffected by pleasure or pain or any other emotion. All change, all character belong to prakriti. There does not seem to be any basis for the attribution of distinctness to purushas. If each purusha has the same features of consciousness, all-pervadingness, if there is not the slightest difference between one purusha and another, since they are free from all variety, then there is nothing to lead us to assume a plurality of purushas. Multiplicity without distinction is impossible (Indian Philosophy, vol. II, p. 322).

The incompatibility between empirical and absolute knowledge

As a result of the opposed nature of purusha and prakriti, the Samkhya-Yoga metaphysics encounters problems in establishing harmony between empirical and absolute knowledge. Here is how S. Radhakrishnan comments on this puzzling aspect:

When the Samkhya breaks up the concrete unity of experience into the two elements of subject and object and makes them fictitiously absolute, it cannot account for the fact of experience. When purusha is viewed as pure consciousness, the permanent light which illuminates all objects of knowledge, and prakriti as something opposed to consciousness and utterly foreign to it, the latter can never become the object of the former. The Samkhya cannot get across the ditch which it has dug between the subject and the object. [...] Unless the subject and object are akin to each other, how can the one reflect the other? How can buddhi, which is non-intelligent, reflect purusha? How can the formless purusha which is the constant seer be reflected in buddhi which is changing? The two cannot, therefore, be absolutely opposed in nature (Indian Philosophy, vol. II, p. 303-4).

No possible relationship can exist between empirical knowledge, which belongs to the domain of prakriti, and the absolute knowledge of purusha. Because they belong to different realms, on the one hand purusha cannot know prakriti, and on the other hand, prakriti and all its forms cannot do anything to help liberation.

An attempt to solve this difficulty was made by postulating the fact that prakriti operates instinctively for purusha's liberation. The Samkhya-Sutra (3,47) states that "creation (prakriti) works for the sake of purusha, so that it may attain supreme knowledge." The Yoga-Sutra of Patanjali (2,21) also mentions that prakriti exists only for the sake of serving purusha's liberation. But in the absence of an external agent who could "inspire" a teleological instinct to prakriti, the difficulty is not solved. Samkhya rejects the existence of a creator god, and Ishvara of the Yoga darshana is not a personal god, but rather a macro-purusha that was never involved with psycho-mental activity or the law of karma (Yoga-Sutra 1,24), being devoid of any creative abilities.

The teleological instinct of prakriti was illustrated in the Samkhya and Yoga darshanas by the image of a horse that pulls a wagon out of instinct, an act to which the wagon driver is a simple spectator. In the same way, prakriti would conduct purusha toward liberation without any external directive. However, it is omitted in this metaphor that the horse was first trained by the driver before he knew the way home. Samkhya metaphysics does not allow such an external "coach" for prakriti. Another deficient illustration used by the Samkhya followers is that of a blind man and a lame man helping each other on their journey. Neither can this be a valid illustration to symbolize the teleological instinct of prakriti, since both the blind man and the lame man possess intelligence and language, and therefore can cooperate in realizing a common purpose. Such cooperation between purusha and prakriti cannot exist, because they have nothing in common. Therefore, the difficulty generated by the impossible relationship between purusha and the psycho-mental abilities cannot be properly solved. How could intellect help to distance purusha from prakriti, if intellect itself is a category of prakriti?

Liberation as isolation

Personhood is considered to be a product of prakriti's manifestation, a sum of psycho-mental experiences that cease to exist at the moment of liberation. Instead of the pantheist view of liberation, consisting of an impersonal merging of the self with the Absolute, the Samkhya and Yoga darshanas state that the liberated self (purusha) remains eternally isolated, devoid of any relation with other purushas (or with Ishvara, in Yoga) and having as the only possibility that of knowing itself. But given the fact that purusha is devoid of any personal attributes, it is hard to grasp what this self-contemplation could mean. As in pantheism, liberation is out of personhood, it does not mean becoming a free person.